NAS 2 CHALLENGE EVALUATION EXAM 2025/2026
ANSWERS AND QUESTIONS GRADED A+
✔✔abdominal - ✔✔spleen, intestines
✔✔pelvic - ✔✔bladder, reproductive organs
✔✔ionic bonds - ✔✔electrons are transferred
✔✔covalent bonds - ✔✔electrons are shared
✔✔hydrogen bonds - ✔✔hydrogen is weakly attracted to a very electronegative atom
✔✔nonpolar covalent bond - ✔✔electrons are shared equally (atoms are roughly
equally electronegative)
✔✔polar covalent bond - ✔✔electrons are not shared equally (atoms are vastly different
in electronegativity)
✔✔decomposition reaction - ✔✔single reactant breaks down to form multiple products
✔✔synthesis reaction - ✔✔multiple reactants combine to form a single product
✔✔exchange reactions - ✔✔multiple molecules exchange reactants to form two new
products
✔✔how do enzymes catalyze reactions? - ✔✔provide a different pathway to get to the
end product with a lower activation energy
✔✔why is water important to life? - ✔✔1. its a solvent
2. many compounds can ionize (convert themselves into an ion by removing electrons)
ex: electrolytes
3. water is very reactive
ex: dehydration synthesis
ex: hydrolysis
4. high heat capacity
ex: thermal inertia
ex: large heat of vaporization
5. lubrication: can reduce friction and build up
6. cushioning: very incompressible--> can compress and stretch easily
✔✔pH - ✔✔[hydrogen ions]
low = acid
high = base
, ✔✔organic compounds - ✔✔carbon-based molecules
✔✔monomer - ✔✔single molecule that can come together to form polymers
✔✔polymer - ✔✔large molecule formed by many repeating units (monomers)
✔✔4 major groups of organic compounds - ✔✔carbs, lipids, proteins, nucleic acids
✔✔protein 3D structure - ✔✔protein structure is based on a few types of bonds that
form between side groups of the protein, this contributes to the bonds it can form with
other molecules
✔✔cell theory - ✔✔idea that all living things are composed of cells, cells are the basic
units of structure and function in living things, and new cells are produced from existing
cells
✔✔requirements for cellular life - ✔✔reproduction, metabolism, growth
✔✔cell cycle - ✔✔series of events that cells go through as they grow and divide
✔✔mitosis - ✔✔part of eukaryotic cell division during which the cell nucleus divides
✔✔steps of mytosis - ✔✔prophase, metaphase, anaphase, telophase
✔✔strucure of DNA - ✔✔repeating sugar phosphate base that connect to antiparrallel
strands via hydrogen bonds between bases.
✔✔dna replication - ✔✔helicase separates antiparrallel strands, dna polymerase I starts
a new chain, dna polymerase III makes it continuously in one direction and staggered in
the other direction, ligase binds the Okazaki fragments togetehr
✔✔transcription - ✔✔making rna from dna
✔✔translation - ✔✔making proteins from rna
✔✔cellular respiration (anaerobic) - ✔✔produce less ATP and lactic acid
✔✔cellular respiration (aerobic) - ✔✔produces a ton of ATP by breaking down glucose
in the presence of oxygen
✔✔steps of cellular respiration - ✔✔glycolysis, citric acid cycle, electron transport chain
✔✔compound light microscope - ✔✔
ANSWERS AND QUESTIONS GRADED A+
✔✔abdominal - ✔✔spleen, intestines
✔✔pelvic - ✔✔bladder, reproductive organs
✔✔ionic bonds - ✔✔electrons are transferred
✔✔covalent bonds - ✔✔electrons are shared
✔✔hydrogen bonds - ✔✔hydrogen is weakly attracted to a very electronegative atom
✔✔nonpolar covalent bond - ✔✔electrons are shared equally (atoms are roughly
equally electronegative)
✔✔polar covalent bond - ✔✔electrons are not shared equally (atoms are vastly different
in electronegativity)
✔✔decomposition reaction - ✔✔single reactant breaks down to form multiple products
✔✔synthesis reaction - ✔✔multiple reactants combine to form a single product
✔✔exchange reactions - ✔✔multiple molecules exchange reactants to form two new
products
✔✔how do enzymes catalyze reactions? - ✔✔provide a different pathway to get to the
end product with a lower activation energy
✔✔why is water important to life? - ✔✔1. its a solvent
2. many compounds can ionize (convert themselves into an ion by removing electrons)
ex: electrolytes
3. water is very reactive
ex: dehydration synthesis
ex: hydrolysis
4. high heat capacity
ex: thermal inertia
ex: large heat of vaporization
5. lubrication: can reduce friction and build up
6. cushioning: very incompressible--> can compress and stretch easily
✔✔pH - ✔✔[hydrogen ions]
low = acid
high = base
, ✔✔organic compounds - ✔✔carbon-based molecules
✔✔monomer - ✔✔single molecule that can come together to form polymers
✔✔polymer - ✔✔large molecule formed by many repeating units (monomers)
✔✔4 major groups of organic compounds - ✔✔carbs, lipids, proteins, nucleic acids
✔✔protein 3D structure - ✔✔protein structure is based on a few types of bonds that
form between side groups of the protein, this contributes to the bonds it can form with
other molecules
✔✔cell theory - ✔✔idea that all living things are composed of cells, cells are the basic
units of structure and function in living things, and new cells are produced from existing
cells
✔✔requirements for cellular life - ✔✔reproduction, metabolism, growth
✔✔cell cycle - ✔✔series of events that cells go through as they grow and divide
✔✔mitosis - ✔✔part of eukaryotic cell division during which the cell nucleus divides
✔✔steps of mytosis - ✔✔prophase, metaphase, anaphase, telophase
✔✔strucure of DNA - ✔✔repeating sugar phosphate base that connect to antiparrallel
strands via hydrogen bonds between bases.
✔✔dna replication - ✔✔helicase separates antiparrallel strands, dna polymerase I starts
a new chain, dna polymerase III makes it continuously in one direction and staggered in
the other direction, ligase binds the Okazaki fragments togetehr
✔✔transcription - ✔✔making rna from dna
✔✔translation - ✔✔making proteins from rna
✔✔cellular respiration (anaerobic) - ✔✔produce less ATP and lactic acid
✔✔cellular respiration (aerobic) - ✔✔produces a ton of ATP by breaking down glucose
in the presence of oxygen
✔✔steps of cellular respiration - ✔✔glycolysis, citric acid cycle, electron transport chain
✔✔compound light microscope - ✔✔
